Atomic Strain

Computes per-atom strain (deformation gradient, strain tensors, D²min) relative to a reference configuration.

Install

vpm install @voltlabs/atomic-strain

CLI

atomic-strain <input_dump> [output_base] [options]

Argument	Required	Default	Description
<input_dump>	yes	—	Input LAMMPS dump.
[output_base]	no	derived from input	Base path for output files.
--reference <file>	no	current frame	Reference LAMMPS dump frame; if omitted, the current frame is used.
--cutoff <float>	no	3.0	Cutoff radius for neighbor search.
--eliminate_cell_deformation	no	false	Eliminate cell deformation before computing strain.
--assume_unwrapped	no	false	Assume coordinates are already unwrapped.
--calc_deformation_gradient	no	true	Compute the deformation gradient F.
--calc_strain_tensors	no	true	Compute strain tensors.
--calc_d2min	no	true	Compute D²min.
--calc_polar_decomp	no	true	Compute the polar decomposition (rotation R and stretch U tensors).
--threads <int>	no	auto	Maximum worker threads.

Exports

Output file	Exposure	Exporter → artifact
{output_base}_atomic_strain.parquet	Atomic Strain	— (listing-only)
{output_base}_atoms.parquet	Atomic Strain Model	AtomisticExporter → glb

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Full input contract and examples: https://docs.voltcloud.dev/docs/plugins/atomic-strain